Towable wheeled backpack

ABSTRACT

A towable, wheeled-backpack includes a towing handle attached to a curved, single-pole, telescoping towing member which retracts into the backpack when not in use. The curvature of the towing member provides support for a backing sheet that is attached to the towing member, and the backing sheet is contoured so that the backpack can be comfortably supported on a wearer&#39;s back. A rigid base with wheels is pivotally attached to a bottom end of the towing member. The pivot attachment allows the base and wheels to move independently of the towing member as the bag is worn or as the bag is rolled along the ground.

BACKGROUND OF THE INVENTION

[0001] (1) Field of the Invention

[0002] This invention pertains to the field of backpacks of the typethat can be worn on a person's back or over a person's shoulder. Moreparticularly, this invention pertains to a wheeled-backpack having aunique, non-rigid or flexible connection between a rigid wheeled base ofthe backpack and a supporting backing sheet of the backpack that restsagainst a person's back when worn. The flexible connection allows thebase and backing sheet to move relative to each other as the backpackwearer's upper body moves, enabling the backpack to be more comfortablyworn. Additionally, a unique curved extendable towing member is utilizedthat follows the curvature of the backpack wearer's back to furtherenhance the comfort of wearing the backpack.

[0003] (2) Background of the Invention

[0004] It is common for many varieties of baggage to be equipped withwheels that enable the baggage to be towed by persons when traveling. Atypical towable piece of baggage generally includes a pair of wheels andan extendable towing member connected to the piece of baggage.

[0005] A typical wheeled-suitcase, for example, has wheels that are onlya few inches in diameter. The wheels are usually mounted spaced apart onan edge of the suitcase where they can support the suitcase above theground when the suitcase is tilted and towed. Although some suitcasehave retractable wheels and some have casters, most suitcases havewheels that are fixed in a single orientation relative to an edge of thesuitcase.

[0006] It is also common for the wheels of such towable baggage to bemounted to a rigid base of the piece of baggage. The rigid base hassufficient stiffness to support the wheels in their fixed orientationand to support the weight of the piece of baggage and its contents whenbeing towed. In the case of a rigid wheeled-suitcase having a shell madeof plastic, aluminum, or other generally stiff material, the rigid baseis often merely a portion of the suitcase exterior. Conversely, baggagemade mostly of canvas, nylon, leather, or other flexible materialsgenerally utilize some form of stiffening frame or rigid base adjacentthe exterior of the baggage for supporting the weight and holding thewheels in their fixed orientation.

[0007] As mentioned above, a wheeled pieced of baggage also commonlyincludes some form of towing member with a towing handle that isextendable from the piece of baggage. Extension of the towing memberallows the piece of baggage to be pulled behind a person without cominginto contact with the person's legs and feet as the piece of baggage isbeing towed.

[0008] In many cases, a wheeled piece of baggage has an extendabletowing member comprised of a pair of parallel telescoping poles bridgedby the towing handle. The poles slide into separate vertically orientedtubular receptacles rigidly attached to an interior compartment of thepiece of the baggage. In such a configuration, the towing member leastinterferes with the internal compartment of the piece of baggage and isgenerally not visible from the exterior of the piece of baggage whenstowed or retracted. Other types of baggage utilize single-poletelescoping tow members that extend and retract from a single tubularreceptacle that is centrally positioned between the wheels of the pieceof baggage.

[0009] Yet other types of baggage utilize non-telescoping extendabletowing members such as bars or poles that are hinged to the piece ofbaggage. Typically, such pieces of baggage have some form of clasp thatholds the towing member against a side of the piece of baggage when thebaggage is not being towed and that releases the towing member whendesired to allow the towing member to pivot upwardly into an extendedposition. Such towing members can also usually be locked into aparticular extended position.

[0010] Providing baggage such as overnight luggage or suitcases withwheels has increased in popularity and their convenience has beenappreciated to the extent that recently, wheels have begun beingprovided on other types of baggage such as backpacks. However, mostbackpacks have merely been provided with the same type of wheeled towingsystems commonly utilized with conventional baggage as described above.Prior art wheeled-backpacks provided with conventional towing systemssuffer from disadvantages due to their different design and constructionfrom that of other types of baggage such as suitcases, and due to theircommonly being worn on the back of the user unlike other types ofbaggage.

[0011] One such disadvantage is that, unlike suitcases, it is desirablethat a backpack be able to flex, especially on the portion of thebackpack that rests against a person's back when being worn. This isbecause, as a person walks, the person's shoulders rotate relative tohis or her hips, thereby causing his or her back to twist. Likewheeled-suitcases, conventional wheeled-backpacks typically have anextendable towing member rigidly attached to the base of the backpack.This is because it was generally thought in the art that the towingmember must be rigidly attached to the base of the piece of baggage toeffectively be used to tilt and tow the piece of baggage along theground. However, the rigid construction of prior art wheeled-backpacksis disadvantaged in that, as a person walks while wearing such abackpack, portions of the backpack are unable to maintain contactagainst the person's back and thereby cause discomfort as theyintermittently contact the person's back. Additionally, as a wearerclimbs stairs or leans to one side such as when reaching down to pick upanother item, one of the wearer's shoulders is momentarily closer to thewearer's hips than the other. In this situation, depending upon theparticular configuration of the backpack, either the bottom or the topof the backpack will slide from side to side causing additionaldiscomfort. These aspects of prior art wheeled-backpacks cause suchbackpacks to feel more like strapped on suitcases rather thanconventional non-wheeled-backpacks which are soft sided and much morecomfortable.

[0012] In addition to the disadvantages in comfort, the rigidconstruction of prior art wheeled-backpacks also suffers from structuraldisadvantages. Unlike suitcases that typically have a rigid rectangularframe or shell for maintaining the shape of the suitcase which also isused to adequately support the towing member, prior artwheeled-backpacks generally lack such a support. Thus, the towing memberof a prior art wheeled-backpack is typically supported by the rigid baseof the backpack on which the wheels are mounted. In this configuration,the towing member acts as a leverage arm creating large stresses at theunion between the towing member and the base even during normal towing.Additional stresses are generated when the wheels of such a backpackattempt to move independently of the towing member, such as when onewheel encounters an obstruction when the backpack is being towed. Insuch a situation, one of the wheels typically rides over the obstructionwhile lifting the other wheel above the ground, thereby causingtorsional loading of the towing member. To withstand these loads, thebase of the towing member of a typical prior art backpack is madesubstantially strong and durable, which limits the materials that mayused to construct the backpack and which influences the weight of thebackpack.

[0013] Yet another disadvantage associated with any type of wheeledbaggage having a rigid construction is that they are prone to tippingover when being towed around corners. This tendency to tip is due to thetowing member functioning as a lever arm which causes a large torque toact upon the baggage when even small forces are applied to the towinghandle.

SUMMARY OF THE INVENTION

[0014] The towable wheeled backpack of the invention overcomes thedisadvantages associated with prior art wheeled-backpacks by providing atowing system uniquely adapted for use with backpacks. The towing systemallows a wheel-backpack to flexibly conform to a person's twisting backwhen being worn, while still maintaining the structural integrity neededto tow the backpack if desired. Thus, the towing system of the inventiongreatly improves the comfort of wearing a wheeled-backpack and actuallyimproves the towability of wheeled-backpacks.

[0015] In general, the invention comprises several elements in commonwith prior art wheeled-backpacks such as shoulder straps, a waist strap,wheels, and an extendable towing member. Unlike prior art backpackshowever, the preferred embodiment of the invention utilizes novelconstructions of the common elements and several additional novelfeatures.

[0016] The preferred embodiment of the wheeled-backpack of the inventioncomprises a pivotal connection between a rigid base portion of thebackpack and an extendable towing member upon which an internalsupporting backing sheet is attached. The pivotal connection allows thebacking sheet to twist relative to the base as a person's shoulderstwist relative to his or her hips when the backpack is being worn. Thiseliminates the discomfort experienced using prior art wheeled-backpackshaving a back fixed relative to the base. Additionally, the pivotalconnection reduces the torsional forces acting on the towing member byallowing the wheels of the backpack to move relative to the towingmember and “step” over obstructions when the backpack is being towed.The pivot connection also reduces unintentional tipping of the backpackdue to sudden forces acting on the towing member, thereby improving thetowability of the back pack while reducing the size and weight of thetowing member.

[0017] The wheeled-backpack of the preferred embodiment also utilizes acurved single-pole telescoping towing member. The curvature of thetowing member follows the contour of the backing sheet which is curvedsimilar to that of a wearer's back rather than being flat or planar asprior art wheeled-backpacks. Additionally, the curvature of the towingmember allows the tow handle to extend upwardly and forward of thebackpack where it is in an optimum position for towing the backpack.

[0018] While the principal advantages and features of the presentinvention have been described above, a more complete and thoroughunderstanding of the invention may be attained by referring to thedrawings and detailed description of the embodiments which follow.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019]FIG. 1 is an isometric view of the preferred embodiment of theinvention showing the backpack with the towing member in a fullyextended position.

[0020]FIG. 2 is an exploded assembly view of the structural componentsof the preferred embodiment of the invention.

[0021]FIG. 3 is an assembly view of the structural components of thepreferred embodiment of the invention shown without the flexible outerpack portion of the backpack.

[0022]FIG. 4 is an isometric assembly view of the preferred embodimentof the invention showing the placement of the structural componentsrelative to the pack portion of the backpack.

[0023] Reference characters in the written specification indicatecorresponding parts throughout the several views of the drawings.

DETAILED DESCRIPTION OF THE INVENTION

[0024] The preferred embodiment of the wheeled-backpack 10 of theinvention is shown in FIG. 1 and, like typical backpacks, comprises apack portion 12 with an opposite front 14 and back 16, opposite top 18and bottom 20, and opposite left 22 and right 24 sides. The pack portion12 of the wheeled-backpack 10 is formed of a woven nylon material orother suitable flexible material and has at least one accessible storagecompartment 26, as shown in FIG. 4, for storing various items to becarried within the backpack. Additionally, like prior art backpacks ingeneral, the wheeled-backpack has a pair of shoulder straps (not shown)and, optionally, a waist strap (not shown) for supporting thewheeled-backpack on a wearer's back. When not being worn, a closeableshroud 28 on the front 14 of the pack portion 12 conceals the shoulderstraps and waist strap therebehind, as shown in FIG. 1, so that thestraps will not drag along the ground or become snagged on other itemswhen the wheeled-backpack 10 is being towed.

[0025] The towing system 30 of the preferred embodiment of thewheeled-backpack 10 is largely concealed within the pack portion 12. Forpurposes of describing the invention, the various components of thetowing system 30 are shown without the pack portion 12 in FIGS. 2 and 3.FIG. 2 shows the components in an exploded isometric view and FIG. 3shows the components in an isometric assembly view. In general, thetowing system 30 of the wheeled-backpack 10 comprises a pair of wheels32 mounted to a rigid base 34, an extendable towing member 36, and abacking sheet 38.

[0026] In the wheeled-backpack 10 of the preferred embodiment, thewheels 32 of the towing system 30 are made of plastic and are pivotallyattached to the rigid base 34 on a pair of axially aligned wheel mounts40 formed within wheel wells 42 on opposite sides of the rigid base. Therigid base 34 is preferably formed as a single monolithic piece ofpolymeric or acetate resin. The base 34 has a bottom portion 44 which isreinforced by a generally vertical portion 46 and the pair of wheelwells 42 that provide suitable stiffness for supporting the weight ofthe items stowed in the storage compartment 26 of the pack portion 12and hold the wheels 32 in alignment when the wheeled-backpack 10 isbeing towed. A protrusion 48 from the vertical portion 46 of the rigidbase 34 is positioned centrally between the wheel wells 42. Theprotrusion 48 has a semi-spherical indentation 50 that forms one half ofa socket portion of a ball-and-socket joint used to connect the rigidbase to the towing member 36 as discussed below.

[0027] The extendable towing member 36 of the wheeled-backpack 10 is asingle-pole curved telescoping member comprised of a tubularnon-extendable portion 52 and preferably two tubular extendable portions54. The non-extendable portion 52 and the extendable portions 54 of thetowing member 36 are preferably made of metal to provide adequatestrength and wear properties to the towing member. The non-extendableportion 52 and extendable portions 54 are slidably engaged with oneanother in a telescoping manner to extend and retract a tow handle 56from the wheeled-backpack 10. The non-extendable portion 52 of thetowing member 36 has an oval cross-section and is arched along itslength to partially conform to the curvature of a person's back. Theextendable portions 54 of the towing member 36 have a similarcross-section to that of the non-extendable portion 52 and are alsocurved such that the extendable portions of the towing member can beselectively retracted within the non-extendable portion of the towingmember or, alternately, extended partially outward from the top end 58of the non-extendable portion as desired. The curvature of the towingmember 36 allows the tow handle 56, which is attached to a free end ofone of the extendable portions 54 of the towing member, to be extendedupwardly and forwardly of the wheeled-backpack 10 along a curved pathuntil reaching a fully extended position as shown in FIG. 1. The ovalcross-section of the non-extendable and extendable portions 52, 54 ofthe towing member 36, in addition to the curvature thereof, prevents theextendable portions from twisting relative to each other as well asrelative to the non-extendable portion of the towing member.

[0028] A ball fitting 60, preferably made of plastic, is attached to thebottom end of the non-extendable portion 52 of the towing member 36. Theball fitting 60 has a spherical exterior dimensioned slightly smallerthan the semi-spherical indentation 50 formed in the protrusion 48 ofthe rigid base 34. During assembly of the towing system 30, the ballfitting 60 is positioned against the semi-spherical indentation 50 ofthe rigid base 34 and a separate retaining member 62 is then attached tothe rigid base for securing the towing member 36 to the rigid base. Theretaining member 62 has a semi-spherical indentation 64 that, combinedwith the semi-spherical indentation 50 of rigid base 34, forms thesocket portion of the ball- and-socket joint which connects the towingmember to the base and allows the towing member 36 to pivot and twistrelative to the rigid base.

[0029] The backing sheet 38 used in the preferred embodiment of thewheeled-backpack 10 is a thin sheet of high density foam or othersimilar resiliently flexible material. The backing sheet 38 ispositioned inside the pack portion 12 between the non-extendable portion52 of the towing member 36 and the front 14 of the pack portion where itfunctions as a cushion and prevents a wearer of the backpack fromfeeling the towing member against his or her back. The backing sheet 38is preferably sewn to the front 14 of the pack portion 12 along oppositeedges 66 of the backing sheet, while the bottom edge 68 of the backingsheet is preferably left unattached. Additionally, a top portion 70 ofthe backing sheet is angled relative to the remainder of the backingsheet and lays adjacent the top 18 of the pack portion 12. The backingsheet top portion 70 has an opening 72 configured to allow passage ofthe towing member 36 therethrough as is discussed below.

[0030] A channel member 74, preferably made of material identical tothat of the backing sheet 38, is used to attach the backing sheet to thetowing member 36 by forming a sleeve around the non-extendable portion52 of the towing member. The channel member 74 is preferably sewn alongits perimeter to the backing sheet 38. The channel member 74 is formedwith a channel portion 76 that is only slightly larger in cross-sectionthan is the non-extendable portion 52 of the towing member 36. Whenattached to the backing sheet 38, the channel member holds the backingsheet against the curvature of the towing member to provide the backingsheet with a similar curvature. This configuration allows the backingsheet 38 to twist and slide vertically relative to the towing member 36,within the limitations of the pack portion 12 and the connection of thetop 70 of the backing sheet 38 to the towing member 36.

[0031] In addition to the main components of the towing system 30described above, the preferred embodiment of the wheeled-backpack 10utilizes several other components to attach the towing system to thepack portion 12. One such component is a lower sheet 78 that ispreferably made of material identical to that of the backing sheet 38.The lower sheet 78 is molded to generally conform to the shape of therigid base 34 of the towing system 30. The lower sheet 78 is sewn to theinside of the pack portion 12 adjacent the bottom 20 of the pack portionwhere it separates the rigid base 34 from the pack portion. In thisposition, the lower sheet 78 provides a cushion between the rigid base34 of the towing system 30 and a wearer's back when the wheeled-backpack10 is being worn and also prevents the pack portion 12 of thewheeled-backpack from abrading against the rigid base.

[0032] The backpack also comprises a pair of identical hub plates 80that are preferably made of material identical to that of the rigid base34. The hub plates 80 each have an opening 82 dimensioned to allowpassage of the wheel mounts 40 of the rigid base 34 therethrough. Thehub plates are attached by threaded fasteners 84 to the wheel wells 42of the rigid base 34 from the exterior of the pack portion 12. Thus, thehub plates 80 and the rigid base 34 “sandwich” the pack portion 12 andlower sheet 78 therebetween to attach the rigid base to the pack portionwhile avoiding creating any areas on the material of the pack that wouldwear quickly due to their attachment to the base. Additionally, the hubplates 80 also act to hold the bottom 20 and sides 22, 24 of the packportion 12 tight against the wheel wells 42 to prevent the pack portionfrom interfering with the rotation of the wheels 32.

[0033] Interior 86 and exterior 88 sleeves further secure the towingmember 36 to the pack portion 12. The exterior sleeve 88 has an opening90 for passage of the towing member 36 therethrough and a cup shapedportion 92 configured to receive the tow handle 56 therein when thetowing member is in the retracted position. The interior socket 86 alsohas an opening 94 for passage of the towing member 36 therethrough and acup portion 96 configured to receive the cup shaped portion 92 of theexterior sleeve 88. The interior and exterior sleeves 86, 88 are securedto each other by threaded fasteners with the pack portion 12 and the top70 of the backing sheet 36 “sandwiched” therebetween and with the topend 58 of the non-extendable portion 52 of the towing member 36positioned in the openings of each sleeve. Thus, like the hub plates 80,the interior and exterior sleeves 86, 88 are configured to connect thetop 18 of the pack portion 12 to the towing member 36 without creatingany areas on the material of the pack that could potentially wearquickly due to their attachment to the sleeves.

[0034] Once assembled as described above, the preferred embodiment ofthe wheel-backpack 10 can be worn by a person like a standardnon-wheeled-backpack by opening the closeable shroud 28 and using theshoulder straps and waist strap therebehind. When so doing, the towingmember 36 can be retracted with the tow handle 56 neatly positioned outof the way in the cup shaped 92 portion of the exterior sleeve 88 at thetop 18 of the pack portion 12. Additionally, in this configuration, thecloseable shroud 28 can be tucked away into a pocket (not shown) at thebase of the front 14 of the pack portion 12.

[0035] When being worn as described above, the configuration of theball-and-socket joint between the rigid base 34 and the towing member 36of the wheeled-backpack 10 allows the towing member to pivot in multipleplanes relative to the rigid base, including rotation about a verticalaxis. As a wearer walks or runs, the pivotal connection allows the rigidbase 34 to tilt from side to side and to twist relative to the towingmember 36 and the backing sheet 38 such that the rigid base is able tomove with the wearer's hips without causing the rest of thewheeled-backpack 10 to shift back and forth. Additionally, because thebacking sheet 38 is free to rotate about the towing member 36 andbecause the towing member is free to pivot relative to the base 34, theupper portion of the wheeled-backpack 10 can twist relative to lowerportion of the wheeled-backpack so as to maintain maximum contactagainst the person's back, thereby increasing the comfort of wearing thewheeled- backpack.

[0036] When desired, the wheeled-backpack 10 can be removed from thewearer's back and towed along the ground by concealing the straps behindthe closeable shroud 28 and extending the towing handle 56 from the cupshaped portion 92 of the exterior socket 88 as shown in FIG. 1. In thisconfiguration, the front 14 of the pack portion 12 is tilted toward theground with the wheeled-backpack 10 being supported above the ground bythe wheels 32. The position of the tow handle 56 provided by the curvedtelescoping members 52, 54 allows a person to tow the wheeled-backpackbehind his or her self without risk of the wheeled-backpack 10interfering with the person's legs as he or she walks. Additionally, thecurvature of the towing member 36 also keeps the wheeled-backpack 10more upright than would a towing member that extends straight upwardsfrom the piece of baggage, resulting in a more preferable weightdistribution toward the wheels 32 and away from the tow handle 56.Furthermore, the pivotal connection between the towing member 36 and therigid base 34 reduces the bending moment that would otherwise be inducedin a rigid non-pivotal joint between a conventional towing member andrigid base as the wheeled-backpack 10 is rolled over obstructions.Finally, the “towability” of the wheeled-backpack 10 is improved overprior art wheeled-backpacks because the wheels 32 are allowed to “stepover” obstructions independently without also tilting the entire packportion 12 and because the wheeled-backpack is less likely to tip-overas side forces are applied to the tow handle 56 when towing thewheeled-backpack around a corner.

[0037] It should be understood that in the wheeled-backpack 10 of thepreferred embodiment, the pivotal movement of the towing member 36relative to rigid base 34 is ultimately limited by the configuration ofthe ball-and-socket joint and it should be apparent that at certainangles of pivot, the non-extendable portion 52 of the towing member 36would engage the rigid base 34 or the retaining member 62 of the jointwhich would prevent further movement in a given direction. However, thewheeled-backpack 10 of the preferred embodiment is configured such thatthe pack portion 12 also acts to limit the permissible movement of thetowing member 36 relative to the rigid base 34 by merely becoming tautand thereby carries most of the bending loads that must ultimately passfrom the towing member to the rigid base.

[0038] It should also be understood that, although the invention hasbeen described above in reference to a specific embodiment, theinvention is not limited to this embodiment and numerous alternativeembodiments or changes to the preferred embodiment could be made aswould be apparent to one of ordinary skill in the art without departingfrom the scope of the invention. For example, the connection between thenon-extendable portion of the towing member and the rigid base could bea pin joint or even a rivet that allows the towing member to pivot inonly one plane relative to the rigid base portion. In anotheralternative embodiment, the towing member could simply be attached tothe baggage without directly engaging a base portion. In such aconfiguration, the backpack itself would act as a pivotal connection. Inyet another alternative embodiment, the rigid base portion could have acompletely different shape or even be eliminated altogether while stillallowing the towing member to pivot relative to the wheels. Yet anotherembodiment could utilize more than a single telescoping member and suchtowing members need not be curved nor telescoping.

[0039] Thus it should be clear that modifications and variations couldbe made without departing from the scope of the invention which shouldbe considered as being limited only by the scope of the following claimsand their legal equivalents.

1-20. (cancelled).
 21. A piece of baggage for use as a backpack, thepiece of baggage comprising: a pack constructed of a flexible material,the flexible material enclosing a hollow interior of the pack; at leasttwo shoulder straps attached to said pack on a first side, said shoulderstraps enabling a user to carry said pack on their back; a rigid baseattached to a bottom of the pack; and a backing sheet attached to saidfirst side of the pack that rests against the user's back when the pieceof baggage is worn as a backpack, the backing sheet and the rigid basebeing twistable relative to each other via the flexible material. 22.The piece of baggage of claim 21, wherein: the backing sheet has acontoured surface that conforms to a user's back when the piece ofbaggage is worn as a backpack.
 23. The piece of baggage of claim 21 canbe used as a backpack and as a hand towed piece of baggage, the piece ofbaggage further comprising: at least two wheels mounted for rotation tothe rigid base; and a towing member operatively connected to the rigidbase intermediate the at least two wheels.
 24. The piece of baggage ofclaim 23, wherein: the towing member is curved and telescopes in anarcuate path between extended and retracted positions relative to thebaggage.
 25. A piece of baggage comprising: a pack for receiving andcarrying objects; at least two wheels mounted for rotation on the packand for supporting the pack when the pack is being towed; and a towinghandle attached to the pack by a curved, telescoping member, thetelescoping member allowing the handle to be selectively extendedupwardly and forwardly from the pack and retracted back toward the packalong an arcuate path curved away from the pack; wherein the at leasttwo wheels have a common axis and the telescoping member is operativelyattached to the pack via a ball-and-socket joint in a manner that allowsthe telescoping member to pivot relative to the axis of the wheels. 26.The piece of baggage of claim 25, wherein: the towing member comprises asingle-pole towing member.